Do the windows operate electrically and do they work now?
Remote keyless entry is controlled by the Body Control Module. This has an internal circuit breaker that trips at about 20A for extended periods, shorter periods for higher power. If there's no window operation, or interior lights, it's possible that the BCM has been disconnected - look under the dash (should be under the dash on the vehicle's right hand side in Australia) for a grey box a little larger than a packet of smokes and make sure it's still plugged in!